Positive impacts of Nile tilapia and predatory sahar on carp polyculture production and profits  

作　　者：Madhav K.Shrestha Mahendra P.Bhandari James S.Diana Ramesh Jaiswal Rama N.Mishra Narayan P.Pandit 

机构地区：[1]Department of Aquaculture and Fisheries,Agriculture and Forestry University,Rampur,Chitwan,Nepal [2]University of Michigan,School of Natural Resources and Environment,440 Church St.Ann Arbor,MI 48109-1041,USA [3]Directorate of Fisheries Development,Kathmandu,Nepal

出　　处：《Aquaculture and Fisheries》2018年第5期204-208,共5页渔业学报（英文）

摘　　要：Carp polyculture is commonly practiced throughout south Asia,but traditional aquaculture methodsoften lead to low fish yields from ponds in this region.Two trials were conducted to evaluate the benefitsof adding Nile tilapia and sahar to carp polyculture ponds.The first trial was conducted in 9 earthenponds for 240 days.This on-station trial stocked ponds with three separate treatments:a)carp only(C);b)carp+tilapia(C+T);and c)carp+tilapia+sahar(C+T+S).Combined net fish yield at harvest wassignificantly higher in the C+T+S trial(2.58±0.10 t·ha^(-1)·crop^(-1))compared to the C trial(2.01±0.26t·ha^(-1)·crop^(-1)).Additionally,gross margin(output value minus input costs)was significantlyhigher in the C+T+S trial(2357±211 USD/ha)compared to the C trial(1300±316 USD/ha),but notcompared to the C+T trial(1569±177 USD/ha).Next,an on-farm trial was conducted in 12 farmer-managed earthen ponds for 165 days.This trial focused on two treatment types:a)C and b)C+T+S.Combined net fish yield at harvest was significantly higher in the C+T+S trial(2.78±0.39 t·ha^(-1)·crop^(-1))compared to the C trial(2.06±0.14 t·ha^(-1)·crop^(-1)).Gross margin was alsosignificantly higher in theC+T+S trial(3219±367 USD/ha)compared to the C trial(1800±250 USD/ha).The use of these alternative species,along with traditional carp,has the ability to increase fish yieldand raise profits in polyculture systems.

关 键 词：CULTURE EARTH treatment 

分 类 号：Q14[生物学—生态学]